#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>

int main(){
    int fd = open("/home/lancer/readfile", O_RDWR);
    char buf[1024 * 1024 * 16];
    while(read(fd, buf, 1024 * 1024 * 16) > 0){
        write(STDOUT_FILENO, buf, 1024 * 1024 * 16);
    }
    return 0;
}